Chlorine
- Formula: Cl2
- Molecular weight: 70.906
- IUPAC Standard InChIKey: KZBUYRJDOAKODT-UHFFFAOYSA-N
- CAS Registry Number: 7782-50-5
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Cl2; Bertholite; Chloor; Chlor; Chlore; Chlorine mol.; Cloro; Molecular chlorine; UN 1017; Diatomic chlorine
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Reaction thermochemistry data
Go To: Top, Gas phase ion energetics data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
+ = Cl3-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 23.7 ± 1.2 | kcal/mol | CIDT | Nizzi, Pommerening, et al., 1998 | gas phase; B |
ΔrH° | 16.70 | kcal/mol | Ther | Robbiani and Franklin, 1979 | gas phase; ΔG≈+1 kcal for Cl- + SO2Cl2 <=> Cl3- + SO2; B |
ΔrH° | <43.60 | kcal/mol | PDis | Lee, Smith, et al., 1979 | gas phase; B |
By formula: C2Cl4 + Cl2 = C2Cl6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -36.70 ± 0.60 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -37. kcal/mol; ALS |
By formula: Cl- + Cl2 = (Cl- • Cl2)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17.0 | kcal/mol | SAMS | Robbiani and Franklin, 1979, 2 | gas phase; based on Cl- + SO2Cl2 <--> Cl3- + SO2; National Bureau of Standards, 1968; M |
By formula: C4F6 + Cl2 = C4Cl2F6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -37.38 ± 0.99 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: C3F6 + Cl2 = C3Cl2F6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -47.15 ± 0.12 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: Cl2 + C2ClF3 = C2Cl3F3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -48.82 ± 0.48 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of Chlorination at 363 °K; ALS |
By formula: Cl2 + C2Cl2F2 = C2Cl4F2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -41.08 ± 0.56 | kcal/mol | Cm | Lacher, McKinley, et al., 1949 | gas phase; Heat of chlorination at 363 °K; ALS |
By formula: C2F4 + Cl2 = C2Cl2F4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -57.32 ± 0.20 | kcal/mol | Cm | Lacher, McKinley, et al., 1949, 2 | gas phase; Chlorination at 90 C; ALS |
By formula: C2H4Cl2 + Cl2 = HCl + C2H3Cl3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -27.8 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: CHCl3 + Cl2 = CCl4 + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -22.30 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: C2H4 + Cl2 = C2H4Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -43.65 ± 0.15 | kcal/mol | Cm | Conn, Kistiakowsky, et al., 1938 | gas phase; At 355 °K; ALS |
By formula: C2H2Cl2 + Cl2 = C2H2Cl4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -40.4 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; Heat of chlorination; ALS |
By formula: BrCl + CClF3 = CBrF3 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.69 ± 0.15 | kcal/mol | Eqk | Coomber and Whittle, 1967 | gas phase; ALS |
+ = C2BrF5 +
By formula: BrCl + C2ClF5 = C2BrF5 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.3 ± 0.6 | kcal/mol | Eqk | Coomber and Whittle, 1967 | gas phase; ALS |
By formula: C2H2Cl2 = C2H2 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 5.1 | kcal/mol | Kin | Laursen and Pimentel, 1989 | gas phase; Photolyses; ALS |
By formula: C4F8 + Cl2 = C4Cl2F8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -44.97 ± 0.31 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957 | gas phase; ALS |
By formula: C5F10 + Cl2 = C5Cl2F10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -45.61 ± 0.40 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957, 2 | gas phase; ALS |
By formula: C2Cl6 = C2Cl4 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 31.7 ± 1.0 | kcal/mol | Eqk | Puyo, Balesdent, et al., 1963 | gas phase; ALS |
By formula: C4F8 + Cl2 = C4Cl2F8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -42.22 ± 0.51 | kcal/mol | Cm | Lacher, Kianpour, et al., 1957, 2 | gas phase; ALS |
By formula: C6H11Cl + HCl = C6H12 + Cl2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -34.20 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
By formula: C6H6 + Cl2 = C6H5Cl + HCl
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -32.0 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
By formula: Cl2 + C2HCl3 = C2HCl5
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -36.2 | kcal/mol | Cm | Kirkbride, 1956 | liquid phase; ALS |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess
View reactions leading to Cl2+ (ion structure unspecified)
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
2.50 ± 0.20 | NBIE | Bowen, Liesegang, et al., 1983 | B |
2.33004 | ECD | Ayala, Wentworth, et al., 1981 | Vertical Detachment Energy: 1.02 eV; B |
2.40 ± 0.20 | NBIE | Dispert and Lacmann, 1977 | B |
2.32 ± 0.10 | Endo | Hughes, Lifschitz, et al., 1973 | B |
2.45 ± 0.15 | NBIE | Baeda, 1972 | B |
2.46 ± 0.14 | IMRB | Dunkin, Fehsenfeld, et al., 1972 | B |
2.38 ± 0.10 | Endo | Chupka, Berkowitz, et al., 1971 | B |
2.52 ± 0.17 | EIAE | DeCorpo and Franklin, 1971 | From CCl4; B |
1.020 ± 0.050 | NBIE | Hubers, Kleyn, et al., 1976 | Stated electron affinity is the Vertical Detachment Energy; B |
3.20 ± 0.20 | NBIE | Lacmann and Herschbach, 1970 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
11.481 ± 0.003 | TE | Yencha, Hopkirk, et al., 1995 | LL |
11.480 ± 0.005 | PE | Van Lonkhuyzen and De Lange, 1984 | LBLHLM |
11.50 | EVAL | Huber and Herzberg, 1979 | LLK |
11.51 ± 0.01 | PE | Potts and Price, 1971 | LLK |
11.48 ± 0.01 | PI | Dibeler, Walker, et al., 1971 | LLK |
11.49 | PE | Cornford, Frost, et al., 1971 | LLK |
11.49 | PE | Anderson, Mamantov, et al., 1971 | LLK |
11.48 ± 0.01 | PI | Watanabe, 1957 | RDSH |
11.49 | PE | Dyke, Josland, et al., 1984 | Vertical value; LBLHLM |
11.59 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
Cl+ | 11.86 ± 0.04 | Cl- | EI | Frost and McDowell, 1959 | RDSH |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Nizzi, Pommerening, et al., 1998
Nizzi, K.E.; Pommerening, C.A.; Sunderlin, L.S.,
Gas-phase thermochemistry of polyhalide anions,
J. Phys. Chem. A, 1998, 102, 39, 7674-7679, https://doi.org/10.1021/jp9824508
. [all data]
Robbiani and Franklin, 1979
Robbiani, R.; Franklin, J.L.,
Formation of the trihalide ion Cl3- in the gas phase,
J. Am. Chem. Soc., 1979, 101, 764. [all data]
Lee, Smith, et al., 1979
Lee, L.C.; Smith, G.P.; Moseley, J.T.; Cosby, P.C.; Guest, J.A.,
Photodissociation and photodetachment of Cl2-, ClO-, Cl3-, and BrCl2-,
J. Chem. Phys., 1979, 70, 3237. [all data]
Kirkbride, 1956
Kirkbride, F.W.,
The heats of chlorination of some hydrocarbons and their chloro-derivatives,
J. Appl. Chem., 1956, 6, 11-21. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Robbiani and Franklin, 1979, 2
Robbiani, R.; Franklin, J.L.,
Negative ion-molecule reaction in sulfuryl halides,
J. Am. Chem. Soc., 1979, 101, 3709. [all data]
National Bureau of Standards, 1968
National Bureau of Standards, US,
Technical Note 270 - 3
in The NBS Tables of Chemical Thermodynamic Properties, 1968. [all data]
Lacher, McKinley, et al., 1949
Lacher, J.R.; McKinley, J.J.; Walden, C.; Lea, K.; Park, J.D.,
Reaction heats of organic fluorine compounds. II. The vapor phase heats of chlorination of some simple fluoroolefins,
J. Am. Chem. Soc., 1949, 71, 1334-1337. [all data]
Lacher, McKinley, et al., 1949, 2
Lacher, J.R.; McKinley, J.J.; Snow, C.M.; Michel, L.; Nelson, G.; Park, J.D.,
Reaction heats of organic fluorine compounds. I. Apparatus and the heat of chlorination of tetrafluoroethylene,
J. Am. Chem. Soc., 1949, 71, 1330-1334. [all data]
Conn, Kistiakowsky, et al., 1938
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A.,
Heats of organic reactions. VII. Addition of halogens to olefins,
J. Am. Chem. Soc., 1938, 60, 2764-2771. [all data]
Coomber and Whittle, 1967
Coomber, J.W.; Whittle, E.,
Bond dissociation energies from equilibrium studies. Part 3.-D(CF3-Cl), D(C2F5-Cl) and the enthalpy of formation of CF3Cl,
Trans. Faraday Soc., 1967, 63, 2656-2667. [all data]
Laursen and Pimentel, 1989
Laursen, S.L.; Pimentel, G.C.,
Matrix-induced intersystem crossing in the photochemistry of the 1,2-dichloroethenes,
J. Phys. Chem., 1989, 93, 2328-2333. [all data]
Lacher, Kianpour, et al., 1957
Lacher, J.R.; Kianpour, A.; Park, J.D.,
Reaction heats of organic halogen compounds. X. Vapor phase heats of hydrobromination of cyclopropane and propylene,
J. Phys. Chem., 1957, 61, 1124-1125. [all data]
Lacher, Kianpour, et al., 1957, 2
Lacher, J.R.; Kianpour, A.; Park, J.D.,
Reaction heats of organic halogen compounds. VIII. The heats of chlorination of perfluorinated butene-1 pentene-1 and isobutene,
J. Phys. Chem., 1957, 61, 584-586. [all data]
Puyo, Balesdent, et al., 1963
Puyo, J.; Balesdent, D.; Niclause, M.; Dzierzynski, M.,
Etude analytique et thermodynamique de la pyrolyse de l'hexachloroethane en phase gazeuse.,
Compt. Rend., 1963, 256, 3471-3473. [all data]
Bowen, Liesegang, et al., 1983
Bowen, K.H.; Liesegang, G.W.; Sanders, R.A.; Herschbach, D.W.,
Electron Attachment to Molecular Clusters by Collisional Charge Transfer,
J. Phys. Chem., 1983, 87, 4, 557-565, https://doi.org/10.1021/j100227a009
. [all data]
Ayala, Wentworth, et al., 1981
Ayala, J.A.; Wentworth, W.E.; Chen, E.C.M.,
Electron attachment to halogens,
J. Phys. Chem., 1981, 85, 768. [all data]
Dispert and Lacmann, 1977
Dispert, H.; Lacmann, K.,
Chemiionization in alkali-halogen reactions: Evidence for ion formation by alkali dimers,
Chem. Phys. Lett., 1977, 47, 533. [all data]
Hughes, Lifschitz, et al., 1973
Hughes, B.M.; Lifschitz, C.; Tiernan, T.O.,
Electron affinities from endothermic negative-ion charge-transfer reactions. III. NO, NO2, S2, CS2, Cl2, Br2, I2, and C2H,
J. Chem. Phys., 1973, 59, 3162. [all data]
Baeda, 1972
Baeda, A.P.M.,
The adiabatic electron affinities of Cl2, Br2, I2, IBr, NO2, and O2,
Physica, 1972, 59, 541. [all data]
Dunkin, Fehsenfeld, et al., 1972
Dunkin, D.B.; Fehsenfeld, F.C.; Ferguson, F.E.,
Thermal energy rate constants for the reactions NO2- + Cl2 → Cl2-, Cl2- + NO2 Ü Cl-, HS- + NO2 Ü NO2-, HS- + Cl2 Ü Cl2-, and S- + NO2 Ü NO2-,
Chem. Phys. Lett., 1972, 15, 257. [all data]
Chupka, Berkowitz, et al., 1971
Chupka, W.A.; Berkowitz, J.; Gutman, D.,
Electron Affinities of Halogen Diatomic Molecules as Determined by Endoergic Charge Exchange,
J. Chem. Phys., 1971, 55, 6, 2724, https://doi.org/10.1063/1.1676487
. [all data]
DeCorpo and Franklin, 1971
DeCorpo, J.J.; Franklin, J.L.,
Electron affinities of the halogen molecules by dissociative electron attachment,
J. Chem. Phys., 1971, 54, 1885. [all data]
Hubers, Kleyn, et al., 1976
Hubers, M.M.; Kleyn, A.W.; Los, J.,
Ion pair formation in alkali-halogen collisions at high velocities,
Chem. Phys., 1976, 17, 303. [all data]
Lacmann and Herschbach, 1970
Lacmann, K.; Herschbach, D.R.,
Collisional Excitation and Ionization of K Atoms by Diatomic Molecules: Role of Ion-pair States,
Chem. Phys. Lett., 1970, 6, 2, 106, https://doi.org/10.1016/0009-2614(70)80144-0
. [all data]
Yencha, Hopkirk, et al., 1995
Yencha, A.J.; Hopkirk, A.; Hiraya, A.; Donovan, R.J.; Goode, J.G.; Maier, R.R.J.; King, G.C.; Kvaran, A.,
Threshold photoelectron spectroscopy of Cl2 and Br2 up to 35 eV,
J. Phys. Chem., 1995, 99, 7231. [all data]
Van Lonkhuyzen and De Lange, 1984
Van Lonkhuyzen, H.; De Lange, C.A.,
High-resolution UV photoelectron spectroscopy of diatomic halogens,
Chem. Phys., 1984, 89, 313. [all data]
Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G.,
Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]
Potts and Price, 1971
Potts, A.W.; Price, W.C.,
Photoelectron spectra of the halogens and mixed halides ICI and lBr,
J. Chem. Soc. Faraday Trans., 1971, 67, 1242. [all data]
Dibeler, Walker, et al., 1971
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E.; Rosenstock, H.M.,
Effect of hot bands on the ionization threshold of some diatomic halogen molecules,
Intern. J. Mass Spectrom. Ion Phys., 1971, 7, 209. [all data]
Cornford, Frost, et al., 1971
Cornford, A.B.; Frost, D.C.; McDowell, C.A.; Ragle, J.L.; Stenhouse, I.A.,
Photoelectron spectra of the halogens,
J. Chem. Phys., 1971, 54, 2651. [all data]
Anderson, Mamantov, et al., 1971
Anderson, C.P.; Mamantov, G.; Bull, W.E.; Grimm, F.A.; Carver, J.C.; Carlson, T.A.,
Photoelectron spectrum of chlorine monofluoride,
Chem. Phys. Lett., 1971, 12, 137. [all data]
Watanabe, 1957
Watanabe, K.,
Ionization potentials of some molecules,
J. Chem. Phys., 1957, 26, 542. [all data]
Dyke, Josland, et al., 1984
Dyke, J.M.; Josland, G.D.; Snijders, J.G.; Boerrigter, P.M.,
Ionization energies of the diatomic halogens and interhalogens studied with relativistic hartree-fock-slater calculations,
Chem. Phys., 1984, 91, 419. [all data]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]
Frost and McDowell, 1959
Frost, D.C.; McDowell, C.A.,
Recent electron impact studies on simple molecules (O2, Cl2, I2),
Advan. Mass Spectrom., 1959, 1, 413. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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